Shock absorber



March 5, 1935. W I O 1,993,703

SHOCK ABSORBER Filed Aug. 29,1951

Wibzeaw Jventor Patented Mar. 5, 1935 v v 1,993,703

UNITED STATES PATENT oFF cl:

SHOCK ABSORBER 7 Walter B. Clifford, Boston, Mass, assignor to Clifford Manufacturing (30., Boston, Mass, a corporation of Delaware Application August 29,1931, Serial-No. 560,203

8 Claims. (01. 1ss ss The present invention'relates to shock absorbers medium preferably being of such a character that for motor vehicles and other apparatus in which it its" condition is not measurably'affected by variais expedient or desirable to limit or confine the tion in temperature of the instrument. I have igbound of a spring by imposing resistance found that amorphous graphite is well suited to -ereon. 7

The purpose of the present invention is to protrusion at a definite rate through a restricted orivide a simple, rugged and effective appliance of fice presenting the necessary resistance independthis character which, in its structural charactenently'of temperature conditions. istics, lends itself admirably to production meth I propose to impart resistance upon movement my purpose, thismaterial being capable of ex- 5 l0 -ods and which in its operation is independent of ofth operating arm in either direction by pro-' l0v temperature conditions and capable of positively viding two pistons spaced at opposite sides of a controlling and checking violent springfmoverestricted orifice and encompassing a shock abments. I sorbing chamber which contains the graphite or With this and other objects in view, thevarious equivalent shock absorbing material. To this end features of the invention consist in certain novel the member 36 is provided with an enlarged cylin- 15' features of construction, combinations and ardrical portion 42 to form one piston, and extending rangements of parts hereinafter described and therebeyond is a cylindrical portion 44 of subclaimed, the advantages of which will be obvious stantially lesser diameter, upon the end of which to thoseskilled in the art from the following d eis mounted a second piston 46 having the same scription 1 I diameter as the piston 42. The second piston is '20 In the accompanying drawing illustrating the clamped against a shoulder 48 by clamping nuts preferred form of the invention, Fig. 1 represents '50. Both pistons are mounted for a sliding fit a section in plan of my improved instrument; and within an Open- Cylinder 52, the Space Fig. 2 is a detail at right angles to Fig. 1, showing tween the pistons being sealed by rings 54. P0-

a section of a portion of the instrument; sitioned in the space encompassed by the pistons 25 Referring particularly to the illustrated emis a restricted orifice provided through an inset bodiment of the invention, the instrument comsleeve 60, having an inner convex surface 62 prises a base portion 10, having an attaching shaped-to form an orifice of gradually restricted surface 12 which is designed to be bolted or otherdiamet r so t o the fashion of Ventuli wise attached directly to the frame of a motor tube. This orifice, which may beindicated at 30 vehicle through bolt'holes 14. The base may be Surrounds the Stem which moves axially of generally rectangular formation, and is prothereof with the pisto .The amorphous gr vided with an outwardly projecting wall 16, which ite contained in the space surrounding the stem in conjunction with a head l8 provides a cham- 44 and between the pistons is forced from one er 20--within which the working portions of the side to the other of the orifice upon movement of 35 shock absorber are self-contained. As indicated the p y P p y Coordinating e fi the absorber may be provided with the usual arm tive size of the orifice and the shape of the con- 22 for attachment through a 11m; to the movable vex surface 62, t e instrument c be caused to portion of the apparatus such as the axle, this p ese a light resistance t0 Smell movements,

fn 22 being keyed'to the outer end 24 of an and an increasing resistance to movements of 40 oscillating shaft 26 which is journaled in bearings greater amplitude,,which is a desirable character- 28 and 30 formed respectively in the base 10 and iStiC in apparatus of this kindhead 18, as shown particularly in Fig. v1. The 'Reference to the drawing will indicate that the shaft 26 is provided with an eccentric portion 32, inset Sleeve 60 i5 Slipped Within the Cylinder and which may be surrounded by an eccentric sleeve locked by a pin 65. The cylinder is preferably 45 or strap 34, forming a part of a reciprocating provided with integral trunnions '70, which are member 36. As will be evident, the purpose of swivelled in bearings 72 formed respectively in this constructionisto convert the oscillating mothe base 10 and head 18 to permitv a slight tion of the arm 22 into a reciprocatory motion oscillation of the shock absorbing assembly withof predetermined extent of the member 36. The in the housing due to the motionof the eccen- 5o shaft 26 at the point where it emerges from the trio 32. The chamber provided by the base 10 cap 18 may be stuffed, as at 38, with a gland 40. and head 18, and indicated generally at 20, is

The shock absorbing function of the instruintercommunicating at opposite sides of the cylment is accomplished by extruding .a plastic or inder, this chamber being preferably filled with fluid medium through a restricted orifice, this oil for lubrication purposes. In the normal op- 55 eration of the instrument there is no intercommunication between the graphite-filled chamber and the outer surrounding oil chamber, due to the hermetic seal formed by the pistons and rings. The head is conveniently secured in the base by threaded members 74, and a gasket may be provided for sealingin the lubricating oil.

This construction provides a rugged, positivelyoperating assembly which resists violent motion, and is comparatively cheap and simple to manufacture, as the base, head and shock absorbing cylinder may be formed as forgings, and substantially all of the machine portions are either round holes or cylindrical surfaces. The fact that all the moving parts are sealed within the housing and subjected to the lubricating efiect of oil within the chamber 20 eliminates substantial wear, and insures that the instrument shall operate effectively without servicing for long continued periods.

What is claimed is: i r

1. A shock absorber comprising I a two-part housing, a cylinder oscillatably supported within the housing, opposed pistons sliding within'the cylinder, operating connections for the pistons extending without the housing, a restricted orifice located between the pistons and graphitic. material contained within the space between the pistons and designed to be forced through the orifice upon movement of the pistons in either direction.

2. A shock absorber comprising a cylinder having trunnions formed thereon, an inset sleeve having a generally convex inner surface connected to the cylinder, opposed pistons sliding within the cylinder at opposite sides of the sleeve, graphite contained within the space between the pistons, a two-part housing having a chamber in which the cylinder and pistons are received, bearings on the housing for supporting the trunnions, and operating connections for the pistons extending without the housing.

3. A shock absorber comprising a cylinder having trunnions formed thereon, an inset sleeve having a generally convex inner surface connected to the cylinder, opposed pistons sliding within the cylinder at opposite sides of the sleeve, graphite contained within the space between the pistons, a two-part housing having a chamber in which the cylinder and pistons are received, bearings on the housing for supporting the trunnions, a shaft oscillatably supported within the housing and extending without the housing, an arm connected to the outer end of the shaft, and connections between the shaft and piston forreciprocating the pistons upon oscillation of the shaft.

4. A shock absorber comprising a cylinder having trunnions formed thereon, an inset sleeve having a generally convex inner surface connected to the cylinder, opposed pistons sliding within the cylinder at opposite sides of the sleeve, graphite contained within the space between the pistons, a two-part housing having a chamber in which the cylinder and pistons are received, bearings on the housing for supporting the trunnions, a shaft oscillatably supported in the housing, an eccentric on the shaft, connections between the pistons and eccentric, and an arm connected to the shaft without the housing.

5. A shock absorber comprising a restricted orifice flaring outwardly at opposite ends, a chamber communicating with the orifice, amorphous graphite contained within the chamber, a piston for forcing the graphite through the restricted orifice upon movement thereof, and means connected with the piston for actuating the latter in accordance with vehicle spring movement.

6. A shock absorber comprising pistons en compassing a shock absorbing space, a restricted orifice dividing the space except for communication therethrough, amorphous graphite contained within the space and designed to be extruded through the orifice upon movement of the pistons in either direction, and means for operating the pistons together.

7. A shock absorber comprising a shock absorbing cylinder having a restricted orifice, amorphous graphite contained within the cylinder, a piston slidingly received within the cylinder and designed to force the graphite through the restricted orifice upon movement thereof, operating connections for actuating the piston in accordance with vehicle spring movement, and a housing enclosing the shock absorbing cylinder and pistons and having a lubricating chamber within which the moving parts are received.

8. A shock absorber comprising a shock absorbing cylinder having a restricted orifice, amorphous graphite contained within the cylinder, a piston slidingly received within the cylinder and designed to force the graphite through the restricted orifice upon movement thereof, operating connections for actuating the'piston in accordance with vehicle spring movement, a housing, connections between the cylinder and housing permitting rocking movements of the cylinder therein, and operating connections extending without the housing for moving the piston in timed relation to spring action.

WALTER B. CLIFFORD. 

